Annoucement is quite often used within a company to announce anything new. Zdoo has included it in OA.
1. Create a category
Go to "OA"->"Announcement"->"Category". Enter the categories you want to add and click Save.
2. Add an announcement
Go to "OA"->"Notice" and click "Create". You will see the window pop out as shown below. Write you announcement and click "Save" to post your announcement.
If any questions, feel free to contact us at firstname.lastname@example.org.